The difference between modern plus old air conditionings plus gas furnaces is immense plus is worth talking about. When I was a kid, I enjoyed reading about the early stages of technology, unique ly in the world of Heating plus A/C. I l acquired about the first window air conditioning that was made from only a few different parts. Then I l acquired about the wood gas furnace that was immense in its afternoon. After that I l acquired about central air conditionings plus gas, oil, plus electric gas furnaces. A little later whole-house air purifiers became a immense deal plus every heating plus cooling supplier wanted to get them on their shelves. I enjoyed reading about all of these thingsâ€¦ Now that I am older, I love working on a/c units plus gas furnaces plus building them myself. I also work as an Heating plus A/C serviceman on the side for extra cash. All this to say, I think a lot about both modern plus old Heating plus A/C units, plus I wanted to take a hour to compare themâ€¦ Many people think that technology has advanced so much over the years that an old air conditioning or gas furnace would be ununique to the modern eye. This simply is not true. The truth is, old window air conditionings were structured much like modern window air conditionings, just with simpler internal parts. Old window air conditionings did not, but, have any air filters which does make a immense difference in how well they work. Back in the afternoon, central air conditionings were not unquestionably heard of except for in some of the more wealthy homes. Back then, commercial air conditionings were more of what several normal households have as their central air conditionings.